Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 10 de 10
Filter
Add more filters










Publication year range
1.
PLoS One ; 10(8): e0134287, 2015.
Article in English | MEDLINE | ID: mdl-26252526

ABSTRACT

BACKGROUND: Strategies to enhance the immunogenicity of DNA vaccines in humans include i) co-administration of molecular adjuvants, ii) intramuscular administration followed by in vivo electroporation (IM/EP) and/or iii) boosting with a different vaccine. Combining these strategies provided protection of macaques challenged with SIV; this clinical trial was designed to mimic the vaccine regimen in the SIV study. METHODS: Seventy five healthy, HIV-seronegative adults were enrolled into a phase 1, randomized, double-blind, placebo-controlled trial. Multi-antigenic HIV (HIVMAG) plasmid DNA (pDNA) vaccine alone or co-administered with pDNA encoding human Interleukin 12 (IL-12) (GENEVAX IL-12) given by IM/EP using the TriGrid Delivery System was tested in different prime-boost regimens with recombinant Ad35 HIV vaccine given IM. RESULTS: All local reactions but one were mild or moderate. Systemic reactions and unsolicited adverse events including laboratory abnormalities did not differ between vaccine and placebo recipients. No serious adverse events (SAEs) were reported. T cell and antibody response rates after HIVMAG (x3) prime-Ad35 (x1) boost were independent of IL-12, while the magnitude of interferon gamma (IFN-γ) ELISPOT responses was highest after HIVMAG (x3) without IL-12. The quality and phenotype of T cell responses shown by intracellular cytokine staining (ICS) were similar between groups. Inhibition of HIV replication by autologous T cells was demonstrated after HIVMAG (x3) prime and was boosted after Ad35. HIV specific antibodies were detected only after Ad35 boost, although there was a priming effect with 3 doses of HIVMAG with or without IL-12. No anti-IL-12 antibodies were detected. CONCLUSION: The vaccines were safe, well tolerated and moderately immunogenic. Repeated administration IM/EP was well accepted. An adjuvant effect of co-administered plasmid IL-12 was not detected. TRIAL REGISTRATION: ClinicalTrials.gov NCT01496989.


Subject(s)
AIDS Vaccines/adverse effects , DNA, Viral/adverse effects , DNA, Viral/immunology , Electroporation , HIV Infections/immunology , Immunization, Secondary , Interleukin-12/immunology , AIDS Vaccines/immunology , Adenoviridae/metabolism , Adult , CD8-Positive T-Lymphocytes/immunology , Demography , Double-Blind Method , Enzyme-Linked Immunospot Assay , Female , Flow Cytometry , HIV Antibodies/immunology , Humans , Immunity, Cellular , Immunity, Humoral , Immunization , Interferon-gamma/metabolism , Male , Middle Aged , Placebos , Young Adult
2.
Ann Otol Rhinol Laryngol ; 120(5): 314-9, 2011 May.
Article in English | MEDLINE | ID: mdl-21675587

ABSTRACT

OBJECTIVES: The purpose of this study was to retrospectively examine how monaurally fitted hearing aids affected word recognition scores in patients with bilateral symmetric sensorineural hearing loss. METHODS: Sixty-six patients from 2 separate institutions were included in this study. In addition to having bilateral symmetric sensorineural hearing loss due to presbycusis, each patient had to have worn a single hearing aid for at least 5 months and have valid pre-aid and post-aid audiograms. Word recognition scores were analyzed with a table of confidence levels generated by Thornton and Raffin that determined the probability of differences between word recognition scores. RESULTS: Hearing aids did not improve or preserve word recognition scores to the degree that has been previously reported in the literature. The unaided (control) ear demonstrated a decrease in word recognition scores over time, as was expected from previous studies. The aided ears demonstrated a similar decline in word recognition scores when compared to the unaided ears. When the conventional confidence level of 0.05 was used, the aided ears showed no advantage over the unaided (control) ears. CONCLUSIONS: These findings are not consistent with the acclimatization first reported by Silman et al in 1993. Such a discrepancy in the results calls for further studies to evaluate just how effective unilateral hearing aids are in patients with bilateral symmetric sensorineural hearing loss.


Subject(s)
Hearing Aids/standards , Hearing Loss, Bilateral/rehabilitation , Hearing Loss, Sensorineural/rehabilitation , Speech Perception/physiology , Aged , Aged, 80 and over , Audiometry, Pure-Tone , Female , Follow-Up Studies , Hearing Loss, Bilateral/physiopathology , Hearing Loss, Sensorineural/physiopathology , Humans , Male , Middle Aged , Retrospective Studies , Time Factors
4.
Antimicrob Agents Chemother ; 50(2): 556-64, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16436710

ABSTRACT

A series of 3,5-dioxopyrazolidines was identified as novel inhibitors of UDP-N-acetylenolpyruvylglucosamine reductase (MurB). Compounds 1 to 3, which are 1,2-bis(4-chlorophenyl)-3,5-dioxopyrazolidine-4-carboxamides, inhibited Escherichia coli MurB, Staphyloccocus aureus MurB, and E. coli MurA with 50% inhibitory concentrations (IC50s) in the range of 4.1 to 6.8 microM, 4.3 to 10.3 microM, and 6.8 to 29.4 microM, respectively. Compound 4, a C-4-unsubstituted 1,2-bis(3,4-dichlorophenyl)-3,5-dioxopyrazolidine, showed moderate inhibitory activity against E. coli MurB, S. aureus MurB, and E. coli MurC (IC50s, 24.5 to 35 microM). A fluorescence-binding assay indicated tight binding of compound 3 with E. coli MurB, giving a dissociation constant of 260 nM. Structural characterization of E. coli MurB was undertaken, and the crystal structure of a complex with compound 4 was obtained at 2.4 A resolution. The crystal structure indicated the binding of a compound at the active site of MurB and specific interactions with active-site residues and the bound flavin adenine dinucleotide cofactor. Peptidoglycan biosynthesis studies using a strain of Staphylococcus epidermidis revealed reduced peptidoglycan biosynthesis upon incubation with 3,5-dioxopyrazolidines, with IC50s of 0.39 to 11.1 microM. Antibacterial activity was observed for compounds 1 to 3 (MICs, 0.25 to 16 microg/ml) and 4 (MICs, 4 to 8 microg/ml) against gram-positive bacteria including methicillin-resistant S. aureus, vancomycin-resistant Enterococcus faecalis, and penicillin-resistant Streptococcus pneumoniae.


Subject(s)
Anti-Bacterial Agents/pharmacology , Carbohydrate Dehydrogenases/antagonists & inhibitors , Gram-Positive Bacteria/drug effects , Pyrazoles/pharmacology , Carbohydrate Dehydrogenases/chemistry , Carbohydrate Dehydrogenases/metabolism , Crystallography , Fluorescence , Microbial Sensitivity Tests , Peptidoglycan/biosynthesis , Protein Binding
5.
Bioorg Med Chem Lett ; 16(1): 176-80, 2006 Jan 01.
Article in English | MEDLINE | ID: mdl-16216496

ABSTRACT

Pulvinones were synthesized (>180) in arrays and evaluated as inhibitors of early stage cell wall biosynthesis enzymes MurA-MurD. Several pulvinones inhibited Mur enzymes with IC(50)'s in the 1-10 microg/mL range and demonstrated antibacterial activity against Gram-positive bacteria including methicillin-resistant Staphyloccus aureus, vancomycin-resistant Enterococcus faecalis, and penicillin-resistant Streptococcus pneumoniae.


Subject(s)
Carboxylic Acids/chemical synthesis , Lactones/chemical synthesis , Streptococcus pneumoniae/metabolism , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Cell Wall/drug effects , Cell Wall/metabolism , Drug Resistance, Bacterial , Enterococcus faecalis/metabolism , Inhibitory Concentration 50 , Methicillin/pharmacology , Microbial Sensitivity Tests , Models, Chemical , Penicillins/pharmacology , Staphylococcus aureus/metabolism , Vancomycin/pharmacology
6.
Bioorg Med Chem Lett ; 15(10): 2527-31, 2005 May 16.
Article in English | MEDLINE | ID: mdl-15863310

ABSTRACT

Over 195 4-alkyl and 4,4-dialkyl 1,2-bis(4-chlorophenyl)pyrazolidine-3,5-dione derivatives were synthesized, utilizing microwave accelerated synthesis, for evaluation as new inhibitors of bacterial cell wall biosynthesis. Many of them demonstrated good activity against MurB in vitro and low MIC values against gram-positive bacteria, particularly penicillin-resistant Streptococcus pneumoniae (PRSP). Derivative 7l demonstrated antibacterial activity against both gram-positive and gram-negative bacteria. Derivatives 7f and 10a also demonstrated potent nanomolar Kd values in their binding to MurB.


Subject(s)
Cell Wall/drug effects , Gram-Positive Bacteria/drug effects , Pyrazoles/pharmacology , Cell Wall/metabolism , Gram-Positive Bacteria/metabolism , Molecular Structure
7.
Bioorg Med Chem Lett ; 14(1): 235-8, 2004 Jan 05.
Article in English | MEDLINE | ID: mdl-14684334

ABSTRACT

Over 50 phenyl thiazolyl urea and carbamate derivatives were synthesized for evaluation as new inhibitors of bacterial cell-wall biosynthesis. Many of them demonstrated good activity against MurA and MurB and gram-positive bacteria including MRSA, VRE and PRSP. 3,4-Difluorophenyl 5-cyanothiazolylurea (3p) with clog P of 2.64 demonstrated antibacterial activity against both gram-positive and gram-negative bacteria.


Subject(s)
Anti-Bacterial Agents/pharmacology , Carbamates/chemistry , Carbamates/pharmacology , Peptidoglycan/biosynthesis , Phenylthiazolylthiourea/analogs & derivatives , Phenylthiazolylthiourea/pharmacology , Cell Wall/drug effects , Cell Wall/enzymology , Enterococcus faecalis/drug effects , Enterococcus faecalis/enzymology , Escherichia coli/drug effects , Escherichia coli/enzymology , Microbial Sensitivity Tests , Staphylococcus/drug effects , Staphylococcus/enzymology
8.
BMC Genomics ; 4(1): 36, 2003 Sep 10.
Article in English | MEDLINE | ID: mdl-12964949

ABSTRACT

BACKGROUND: Cloning of genes in expression libraries, such as the yeast two-hybrid system (Y2H), is based on the assumption that the loss of target genes is minimal, or at worst, managable. However, the expression of genes or gene fragments that are capable of interacting with E. coli or yeast gene products in these systems has been shown to be growth inhibitory, and therefore these clones are underrepresented (or completely lost) in the amplified library. RESULTS: Analysis of candidate genes as Y2H fusion constructs has shown that, while stable in E. coli and yeast for genetic studies, they are rapidly lost in growth conditions for genomic libraries. This includes the rapid loss of a fragment of the E. coli cell division gene ftsZ which encodes the binding site for ZipA and FtsA. Expression of this clone causes slower growth in E. coli. This clone is also rapidly lost in yeast, when expressed from a GAL1 promoter, relative to a vector control, but is stable when the promoter is repressed. We have demonstrated in this report that the construction of libraries for the E. coli and B. subtilis genomes without passaging through E. coli is practical, but the number of transformants is less than for libraries cloned using E. coli as a host. Analysis of several clones in the libraries that are strongly growth inhibitory in E. coli include genes for many essential cellular processes, such as transcription, translation, cell division, and transport. CONCLUSION: Expression of Y2H clones capable of interacting with E. coli and yeast targets are rapidly lost, causing a loss of complexity. The strategy for preparing Y2H libraries described here allows the retention of genes that are toxic when inappropriately expressed in E. coli, or yeast, including many genes that represent potential antibacterial targets. While these methods are generally applicable to the generation of Y2H libraries from any source, including mammalian and plant genomes, the potential of functional clones interacting with host proteins to inhibit growth would make this approach most relevant for the study of prokaryotic genomes.


Subject(s)
Bacillus subtilis/genetics , Escherichia coli/genetics , Genome, Bacterial , Two-Hybrid System Techniques , Bacillus subtilis/metabolism , Cloning, Molecular/methods , DNA, Bacterial/genetics , Escherichia coli/metabolism , Gene Expression , Gene Library , Genetic Vectors/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Reproducibility of Results , Transformation, Genetic , Two-Hybrid System Techniques/standards , Yeasts/genetics , Yeasts/metabolism
9.
Bioorg Med Chem Lett ; 13(19): 3345-50, 2003 Oct 06.
Article in English | MEDLINE | ID: mdl-12951123

ABSTRACT

A series of Muraymycin analogues was synthesized. These analogues showed excellent antimicrobial activity against gram-positive organisms. These analogues also showed excellent inhibitory activity against the target peptidoglycan biosynthesis enzyme MraY, the cell membrane associated transglycosylase responsible for the formation of Lipid II.


Subject(s)
Peptidoglycan/analogs & derivatives , Peptidoglycan/biosynthesis , Peptidoglycan/chemistry , Peptidoglycan/pharmacology , Microbial Sensitivity Tests , Nucleotides , Peptides , Structure-Activity Relationship , Urea
10.
Bioorg Med Chem Lett ; 13(15): 2591-4, 2003 Aug 04.
Article in English | MEDLINE | ID: mdl-12852973

ABSTRACT

Twenty-five 2-phenyl-5,6-dihydro-2H-thieno[3,2-c]pyrazol-3-ol derivatives were synthesized for evaluation as new inhibitors of bacterial cell wall biosynthesis. Many of them demonstrated good inhibitory activity against Staphylococcus aureus MurB, MurC and MurD enzymes in vitro and antimicrobial activity against gram-positive bacteria including MRSA, VRE and PRSP. However, when they were tested in the presence of 4% bovine serum albumin, the MIC values increased to greater than 128 microg/mL against PRSP. None of the compounds demonstrated activity against gram-negative bacteria at MIC <32 microg/mL.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Cell Wall/metabolism , Staphylococcus aureus/metabolism , Anti-Bacterial Agents/pharmacology , Cell Wall/drug effects , Drug Resistance, Bacterial , Genes, Bacterial/genetics , Gram-Positive Bacteria/drug effects , Microbial Sensitivity Tests , Staphylococcus aureus/drug effects , Staphylococcus aureus/enzymology
SELECTION OF CITATIONS
SEARCH DETAIL
...